Molecular chaperones play key roles in protein folding, transport across membranes, and in response to stressful stimuli. Hsc20 is a DnaJ-type "co-chaperone" protein encoded in a recently discovered operon in E. coli which also encodes a DnaK/hsp70-type chaperone. To date, no structure for a DnaJ co-chaperone has been determined. We have recently succeeded in overexpresing, purifying and crystallizing Hsc20. Thus, Hsc20 could provide the first complete high resolution crystal structure for proteins of this class.